961561 has 8 divisors (see below), whose sum is σ = 1016064. Its totient is φ = 908160.

The previous prime is 961549. The next prime is 961567. The reversal of 961561 is 165169.

961561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 961561 - 2⁵ = 961529 is a prime.

It is a Duffinian number.

961561 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (961567) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2016 + ... + 2446.

It is an arithmetic number, because the mean of its divisors is an integer number (127008).

2⁹⁶¹⁵⁶¹ is an apocalyptic number.

It is an amenable number.

961561 is a deficient number, since it is larger than the sum of its proper divisors (54503).

961561 is a wasteful number, since it uses less digits than its factorization.

961561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 551.

The product of its digits is 1620, while the sum is 28.

The square root of 961561 is about 980.5921680291. The cubic root of 961561 is about 98.7019228664.

The spelling of 961561 in words is "nine hundred sixty-one thousand, five hundred sixty-one".